There is available a video display device for displaying video on a monitor of, e.g., a home-use television set receiver and the like connected thereto, and reproducing sound via a speaker of the same. Also, some of the video display devices are portable video display devices which can be carried by a user. As one example, these video display devices read encoded video data and sound data from a computer readable information storage medium, such as a DVD, a hard disk, and the like, and then based on the read data, produces video data for display, in accordance with the capacity (size of the display screen and the like) of a monitor, and sound data for reproduction, in accordance with the capacity (the number of reproduction channels and the like) of a speaker. Then, the produced video data is displayed on the monitor and the produced sound data is reproduced via the speaker.